The old man has left by yellow crane. This sentence comes from the Yellow Crane Tower written by Cui Hao, a poet in the Tang Dynasty. The original text is as follows:

The fairy of the past has flown away by the yellow crane, leaving only an empty Yellow Crane Tower.

The yellow crane never revisited earth, there have been no long white clouds for thousands of years.

Every tree in Hanyang has become clear due to sunlight, and Nautilus Island is covered with sweet grass.

But I looked home, and the twilight was getting thicker. The river is shrouded in mist, which brings people deep melancholy.

The ancients in this poem refer to "immortals of the past".

The immortal has flown away with the Yellow Crane, leaving only an empty Yellow Crane Tower here. The yellow crane never came back. For thousands of years, it only saw long white clouds. Hanyang trees are clearly visible in the sun, and Parrot Island is covered with a piece of green grass. It is getting late. Looking into the distance, where is my hometown? In front of me, I saw a mist hanging over the river, which brought people deep sorrow.